CVE-2026-43921 Details
Description
FOSSBilling is a free, open-source billing and client management system. Versions 0.6.10 through 0.7.2 have a PHP code injection vulnerability in FOSSBilling's `Config::prettyPrintArrayToPHP()` method. When configuration values are updated, string values are written into `config.php` without escaping single quotes. Because `config.php` is loaded via a bare `include` on every HTTP request, an attacker with admin privileges can inject arbitrary PHP code that executes on every subsequent request. Version 0.8.0 contains a patch. Some workarounds are available. Restrict admin access to trusted personnel only; audit `config.php` for unexpected PHP code; and/ or at the reverse proxy/WAF level, restrict access to admin API endpoints that modify configuration.
A PHP code injection vulnerability has been identified in FOSSBilling versions 0.6.10 prior to 0.7.2. The issue arises in the 'Config::prettyPrintArrayToPHP()' method, where string values are written into 'config.php' without properly escaping single quotes. This flaw allows an administrator with access to the admin API to inject arbitrary PHP code that executes with the privileges of the web server user on every HTTP request. The vulnerability is rooted in the configuration serialization process, which fails to sanitize user-supplied input before persisting it.
Users can upgrade to FOSSBilling version 0.8.0, which addresses this vulnerability. Additionally, it's recommended to restrict admin access to trusted personnel, audit 'config.php' for any unexpected PHP code, and at the reverse proxy or WAF level, limit access to admin API endpoints that can modify configuration.
Metrics
CVSS 4.0 Severity and Vector Strings:
VolerionCVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed Jul 6, 2026CISA-ADP
Assessed Jul 7, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/FOSSBilling/FOSSBilling/security/advisories/GHSA-v4j9-w6pj-38w5 | [email protected] | AdvisoryRemedyVendor |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-94 | Improper Control of Generation of Code ('Code Injection') | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| FOSSBilling | >= 0.6.10, <= 0.7.2 (semver) |
CPE
Remediation
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Change History
2 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jul 7, 2026 | CVE Modified | CISA-ADP |
| Jul 6, 2026 | New CVE Received | [email protected] |